Boot is the term for anything of value an exchanger receives out of a 1031 transaction that is not like-kind replacement real property, and it is taxable to the extent of the realized gain even when the rest of the exchange defers cleanly. An Indianapolis owner can run every other part of an exchange correctly, use a qualified intermediary, meet both deadlines, and still owe tax that year because boot slipped into the transaction, usually without anyone intending it to. Understanding the two main forms boot takes, cash and mortgage relief, is what keeps a deferral complete rather than partial.
Cash Boot: Money That Touches the Exchanger's Hands
Cash boot happens whenever an exchanger receives sale proceeds directly rather than routing every dollar through the qualified intermediary into the replacement purchase. This can be as obvious as pocketing leftover funds after buying a smaller replacement property, or as easy to overlook as using exchange proceeds to pay a non-transaction cost at closing, such as a prorated rent credit that functions as cash in the exchanger's favor. Any proceeds left over after the replacement purchase closes, even a modest amount, become cash boot the moment the exchange period ends.
Mortgage Boot: Debt Relief Counts Too
Mortgage boot, sometimes called debt relief, occurs when the debt paid off on the relinquished property is greater than the debt taken on for the replacement property. An owner who pays off a $600,000 loan on a Greenwood retail building but only finances $400,000 on the replacement has $200,000 of debt relief, and that relief is treated as boot unless it is offset by adding new cash into the deal. This is one of the more counterintuitive boot triggers, since the owner never receives that $200,000 as cash, yet it is still taxed as if they did.
How Buying Down in Value Creates Boot Automatically
The general rule for a full deferral is that the replacement property has to be equal to or greater than the relinquished property in both purchase price and debt. An Indianapolis exchanger who sells a $1.2 million industrial building near the airport and buys a $950,000 replacement in Plainfield has bought down by $250,000, and that gap becomes boot regardless of how the transaction is otherwise structured. This is why replacement property searches in this market often start with a target price floor rather than treating the relinquished sale price as a rough guideline.
Offsetting Debt Relief With New Cash
An exchanger who wants to reduce leverage on the replacement property without triggering mortgage boot can add outside cash to the purchase to offset the lower debt, since new cash contributed by the exchanger is not itself boot. Bringing an extra $150,000 to closing on a Fishers multifamily purchase to compensate for a smaller loan than the one paid off on the relinquished property keeps the exchange whole, even though the debt structure looks very different on each side.
Modeling Boot Before an Offer Is Written
The cleanest way to avoid an unwelcome tax bill is comparing the relinquished property's sale price and payoff debt against a candidate replacement's purchase price and anticipated financing before an offer goes in, not after the purchase agreement is already signed. An Indianapolis exchanger evaluating two comparable industrial buildings near Plainfield, one financed at 60 percent leverage and one at 50 percent, will land in a meaningfully different boot position depending on which loan structure is used, even if the purchase prices themselves are nearly identical.